In recent years, display devices are widely used in a smartphone, a personal assistant device (PAD), a tablet computer, a car navigation system, and the like. There is a need for the display devices to make their display regions larger within the same housing size in order to achieve high-definition display, and therefore the frames of the display devices are narrowed by shortening the distance of a non-display part from an outer edge to a display region. Also, light leakage is prevented in the display devices.
See, for example, U.S. Patent Application Publication No. 2015/0241731.